A108664 - OEIS

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A108664

In the decimal expansion of Pi, lengths of sublists ending with 9.

6, 7, 2, 16, 8, 4, 2, 1, 10, 3, 4, 17, 1, 20, 22, 7, 15, 25, 11, 7, 3, 3, 6, 9, 6, 33, 2, 10, 25, 10, 34, 3, 5, 5, 12, 3, 32, 3, 8, 15, 2, 2, 4, 11, 7, 19, 1, 5, 17, 5, 9, 2, 3, 26, 2, 4, 9, 7, 4, 11, 8, 22, 42, 3, 19, 6, 11, 11, 4, 3, 4, 8, 1, 8, 4, 14, 6, 9, 1, 14, 1, 1, 1, 1, 1, 5, 5, 1, 5, 11

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OFFSET

1,1

COMMENTS

Take the decimal expansion of Pi: s={3,1,4,1,5,9,2,6,5,3,5,8,9,7,9,3, 2,3,8,4,6,2,6,4,3,3,8,3,2,7,9,5,0,2,8,8,4}. Split s into sublists each ending with 9: {{3,1,4,1,5,9}, {2,6,5,3,5,8,9}, {7,9}, {3,2,3,8,4,6,2,6,4,3,3,8,3,2,7,9}, {5,0,2,8,8,4,1,9}}. The sequence gives the lengths of the sublists: 6,7,2,16,8,4,2,1,10,3,4,17,1,20,22,7. Cf. A053753 (positions of 9's in the decimal expansion of Pi).

LINKS

Table of n, a(n) for n=1..90.

FORMULA

a(n) = A053753(n+1) - A053753(n).

CROSSREFS

Cf. A000796, A037007, A053753, A108663, A139727, A014974.

Sequence in context: A316165 A267251 A259526 * A160155 A277135 A153628

Adjacent sequences: A108661 A108662 A108663 * A108665 A108666 A108667

KEYWORD

base,nonn

AUTHOR

Zak Seidov, Jun 17 2005

STATUS

approved